Study On The Traveling System Of HT20 Crawler Carriers With Hydraulic And Mechanical Hybrid Transmission

Carriers are a kind of transport vehicle widely used in water conservancy construction project,civil engineering construction projects and mining operations.There are two types of carriers: wheeled and crawler.The crawler carriers have a unique advantage in the operation of sand,marsh and mine due to its large grounding area and good off-road performance.At present,the domestic market is mainly dominated by wheeled carriers,and the transmission mode is a single mechanical,hydraulic or hydraulic transmission.Only a few enterprises produce some small and medium-sized crawler carriers and the market of crawler carriers has a larger gap.Therefore,research on high performance crawler carriers has important practical significance.In order to expand the speed range of traveling hydraulic system and improve the efficiency of transmission system,this paper proposes a hydraulic mechanical hybrid transmission of HT20 crawler carriers,and conducted systematic research for its structural scheme,transmission characteristics,parameter matching and modeling simulation of the driving system.By analyzing and comparing the advantages and disadvantages of different hydraulic circuits and confluence devices,proposed a bilateral independent drive transmission scheme.The left and right sides are driven by a set of bivariate pump-bivariable motor systems,and the two motors on each side pass the speed coupling mechanism.The speed regulation principle is described and the speed regulation range is calculated.The speed ratio characteristics is analyzed,torque ratio characteristics and efficiency of the system under different working conditions,and the total system efficiency is calculated.The system pressure is matched according to the pressure drop matching principle.The variable pump and the variable motor are calculated,selected and checked.The theoretical speed of each gear and the transmission ratio of the speed coupling mechanism is calculated.HT20 crawler carrier is established and simulated in AMEsim software and the feasibility of the system in terms of structural scheme and expansion of the speed range.